Re: [PATCH 10/11] ARM: shmobile: r8a7790: Reference DMA channels in SDHI DT nodes

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Geert,

On Monday 04 August 2014 11:01:28 Geert Uytterhoeven wrote:
> On Wed, Jul 16, 2014 at 12:45 AM, Laurent Pinchart wrote:
> > Add references to the transmit and receive DMA channels in the four
> > SDHI nodes.
> > 
> > Signed-off-by: Laurent Pinchart
> > <laurent.pinchart+renesas@ideasonboard.com>
> 
> Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
> 
> but see below for a question (this also applies to other members of the
> R-Car Gen 2 family)...
> 
> > ---
> > 
> >  arch/arm/boot/dts/r8a7790.dtsi | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/arch/arm/boot/dts/r8a7790.dtsi
> > b/arch/arm/boot/dts/r8a7790.dtsi index 465008a..2ea3b2a 100644
> > --- a/arch/arm/boot/dts/r8a7790.dtsi
> > +++ b/arch/arm/boot/dts/r8a7790.dtsi
> > @@ -406,6 +410,8 @@
> >                 reg = <0 0xee140000 0 0x100>;
> >                 interrupts = <0 167 IRQ_TYPE_LEVEL_HIGH>;
> >                 clocks = <&mstp3_clks R8A7790_CLK_SDHI2>;
> > +               dmas = <&dmac0 0xc1>, <&dmac0 0xc2>;
> > +               dma-names = "tx", "rx";
> >                 cap-sd-highspeed;
> >                 status = "disabled";
> >         };
> > @@ -415,6 +421,8 @@
> >                 reg = <0 0xee160000 0 0x100>;
> >                 interrupts = <0 168 IRQ_TYPE_LEVEL_HIGH>;
> >                 clocks = <&mstp3_clks R8A7790_CLK_SDHI3>;
> > +               dmas = <&dmac0 0xd3>, <&dmac0 0xd4>;
> > +               dma-names = "tx", "rx";
> >                 cap-sd-highspeed;
> >                 status = "disabled";
> >         };
> 
> SDHI2 and SDHI3 actually have 2 sets of 2 (TX and RX) DMA channels:
> the normal one, and the "C2" one. However, I didn't get any wiser about this
> "C2" by browsing through the docs.

I didn't either, so I've decided to ignore them for now. It's funny sometimes 
how life gets simpler when you selectively ignore information ;-)

More seriously, if anyone has any information regarding what the "C2" channels 
are, that would be appreciated.

-- 
Regards,

Laurent Pinchart